FORMS OF LEPRALIA. 451 



mistaken for one of these objects. It is a British species, and the specimen is repre- 

 sented of the natural size. 



The next few figures represent examples of an interesting family of polyzoa called 

 Selenariadae because they are round as the full moon, or Norval's famous shield. In the 

 circular form of the margin they all agree, but differ considerably in their curvatures, 

 some being with one side plane and the other convex, while others are convex-concave, 

 like a watch-glass, or, to speak more accurately, like the lens technically called a 

 meniscus. They are all remarkable for their very large vibracula. 



At fig. O is one of these creatures, Cupularia Lowei, so called on account of its resem- 

 blance to a dome. It is represented of the natural size, but at fig. P is a magnified 



A. Lepralia. (On a shell.) 

 D. Lepralia Gattyae. X 

 G. Lepralia vario!6sa. X 

 J. Lepralia discreta. X 

 M. Eschara flabelldris. X 

 P. Cupularia Lowei. X 

 8. Lunulites cancallatus. 



POLYZOA IV. 



B. Lepralia alata. X 

 E. Lepralia Hydnmanii. X 

 H. Lepralia nitida. X 

 K. Cellepora fusca. 

 N. Eetepora Beaniana. 

 Q. Lunulites capulus. 

 T. Selenaria maculata. 



C. Lepralia mono'ceros. X 



F. Lepralia personata. X 



I. Lepralia Malusii.X 



L. Eschara folie"cea. X 



O. Cupularia Lowei. 



R. Lunulites capulus. 



U. Selenaria maculata. (Section.) 



V. Selenaria maculata. (Section. X) 

 The sign X signifies that the object is magnified. 



portion of the same species, exhibiting the form of the cells and the enormous vibracula 

 with which their mouths are swept. This species is found at Madeira. Fig. Q is the 

 Lunulites capulas of the natural size, and fig. R represents the same species highly 

 magnified, for the purpose of showing the regular arrangement of the cells and the 

 curious vibracula, which in this genus are usually bifid or even trifid at their extremities. 

 Another species of the same genus, Lunulites cancellatus, is given at fig. S. 



At fig. T is shown a very shield-like genus of this family, its name being Selenaria 

 maculata, and a section of the same specimen is given below, at fig. U. The reader 

 will not fail to remark its exact resemblance to the target-shield used by many nations, 

 ancient and modern. Fig. V is a portion of the same species, as it appears when highly 

 magnified, and is given for the purpose of showing the curious vibracula. It may be 

 here mentioned that in this last-mentioned family the vibracula are thought by some 

 naturalists to act as locomotive organs. 



Our space is so rapidly drawing to a close, that it will be hardly possible to give much 



